Interpretive Summary: The pulp of the Amazonian palm fruit, called acai, has been found to have exceptional antioxidant capacity. In this study, a juice blend made from acai was firstly tested by cell-based assays. The results showed that antioxidants in this juice blend could penetrate and protect cells from oxidative damage. They can also reduce several pro-inflammatory factors. Secondly, a randomized, double-blinded, placebo-controlled, crossover trial with 12 healthy subjects was conducted to evaluate antioxidant capacity of this juice blend within the body. Blood samples from different time points were tested using several antioxidant assays, and the antioxidant capacities were confirmed.

Technical Abstract:
This study investigated the in vitro and in vivo antioxidant and anti-inflammatory properties of a juice blend (JB), MonaVie Active, containing a mixture of fruits and berries with known antioxidant activity, including acai, a palm fruit, as the predominant ingredient. The phytochemical antioxidants in the JB are primarily in the form of anthocyanins, predominantly cyanidin 3-rutoside, cyanidin 3-diglycoside, and cyanidin 3-glucoside. The cell-based antioxidant protection of erythrocytes(CAP-e) assay demonstrated that antioxidants in the JB penetrated and protected cells from oxidative damage (p < 0.001), whereas polymorphonuclear cells showed reduced formation of reactive oxygen species (p < 0.003) and reduced migration toward three different pro-inflammatory chemoattractants: fmlp (p < 0.001), leukotriene B4 (p < 0.05), and IL-8 (p < 0.03). A randomized, double-blinded, placebo-controlled, crossover trial with 12 healthy subjects examined the JB's antioxidant activity in vivo. Blood samples at baseline, 1 h, and 2 h following consumption of the JB or placebo were tested for antioxidant capacity using several antioxidant assays and the TBARS assay, a measure of lipid peroxidation. A within-subject comparison showed an increase in serum antioxidants at 1 h (p < 0.03) and 2 h (p < 0.015), as well as inhibition of lipid peroxidation at 2 h (p < 0.01) postconsumption.